This invention relates to test tubes which are adapted to be labeled for identification, content, and other purposes in clinical, research, laboratory and other applications.
The most pertinent prior art known to applicant consists of the following United States patents:
______________________________________ 2,011,659 Soyland 2,045,876 Schwab et al 2,076,345 Johnson et al 2,167,589 Schutz 2,639,554 Zons 2,647,489 Ryckman 3,241,518 Johnson 4,077,355 Miller 4,089,294 Lasiewicz et al ______________________________________
Of these prior patents, the closest is believed to be Zons, U.S. Pat. No. 2,639,554. But neither Zons nor any of the other prior patents discloses the present invention as herein described.
Labeling bands are conventionally painted on test tubes by means of silk screen processes, but none of these processes, to applicant's knowledge, is capable of painting labeling bands in contiguous relation to the open end of the test tubes. Labeling bands, to the extent of their width, obscure the contents of the test tubes and limit their effective capacity. Their effective capacity is further limited to the extent of the spacing between the labeling bands and the open end of the test tubes which results from the use of the silk screen processes.
In the present invention, open-ended tubes (open at both ends) are conveyed to a paint applying station where both ends of each tube are left free to receive paint. The tubes are pre-heated (as in a heat-tempering operation) and they enter the paint applying station at a sufficiently elevated temperature to accelerate the drying of the paint that is applied to them. Following the paint application, the tubes are fused (heat sealed) and severed at the center to form two paint-banded test tubes from each open-ended tube.
Important in the present invention is the method used in applying paint to the open-ended tubes. The tubes are rotated while their ends are in wiping contact with paint applicators that, preferably, are stationary. The location of the paint applicators relative to the ends of the tubes determines the location of the painted band on the tubes. The width of the paint applicators determines the width of the painted band. Alternatively, if the painted band is to be contiguous with the open end of the tubes, the width of the painted band may be adjusted by adjusting the location of the paint applicators axially of the tubes.